Phylum [Vertebrata] (Lamarck, 1801)
   Class †Placodermi McCoy, 1848
     1 Order †Rhenanida Broili, 1930 see Order Rhenaniformes
     2 Order †Ptyctodontida Gross, 1932 see Order Ptyctodontiformes
     3 Order †Arthrodira Woodward, 1891 see Order Arthrodiriformes Grande & Eastman, 1986
     4 Order †Antiarchi Cope, 1885 see Order Antiarchiformes Grande & Eastman, 1986
     5 Genus †Palaeospondylus Traquair, 1890 see Genus Dipterus Sedgwick & Murchison, 1829